You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Wire is an extremely useful material which is used in a variety of ways during orthopaedic surgery. Unfortunately, failures in applying circlage wires are common due to the wire breaking, slipping, or unravelling. 

There are some basic rules to the use of wire which, if not adhered to, will result in failure of the technique.

Wire will snap if the mechanical forces put on it exceed it's strength. This occurs if :

• The guage of the wire is too thin for the purpose. 18G and 20G wire are recommended as a minimum for canine orthopaedic surgery and 20G and 22G for cats.
• The wire is loose allowing movement of the bone and additional pressures and twisting on the wire
• Corrosion due to impurities in the metal
• The wire is not pulled towards the surgeon before each twist during tightening

The wire will unravel if :

• It has not been twisted properly - the wire should be evenly applied, with both wires being twisted around each other, not one wire twisted around a straight piece
• The ends are bent over during twisting
• It has not been tightened sufficiently and there is movement at the site

The wire will slip if :

• The oblique fracture line is not long enough and only one wire can be placed across it. Ideally the fracture line should be twice as long as the diameter of the bone. 
• Wires are not applied at 90⁰ to the shaft of the bone
• Wires are not applied tightly enough
• Other fixation is inadequate and allows movement of the bone (eg rotation) under the wire
• All wires around a bone are not  tightened to the same tension. The tighter wires are subjected to excess stress and will loosen. Use of a tension guage on the wire -tightening instrument helps to control the tension being applied.

Techniques to improve the chances of success are :

• Make a groove with a sharp instrument around the bone for the wire to sit in
• Loop the wire around the bone twice before tightening
• At least 2 wires should be applied along the length of a fracture line
• The wires should be placed at about 2cm intervals along the bone

Updated January 2016